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%I #8 Aug 28 2024 11:26:05
%S 1,0,0,2,0,1,0,6,6,3,0,7,0,11,13,14,0,13,0,13,14,9,0,19,20,24,24,25,0,
%T 23,0,30,30,15,30,31,0,31,37,33,0,37,0,31,43,41,0,43,42,43,44,50,0,49,
%U 53,53,44,27,0,53,0,59,56,62,60,64,0,49,67,67,0,67,0,72,73,69,72,73
%N a(n) = n - A075860(n).
%C If p is a prime number, then a(p)=0.
%e For n=15, a(15) = 15-2 = 13.
%p f := proc(n)
%p option remember:
%p if isprime(n) then
%p n
%p else
%p procname(convert(numtheory:-factorset(n), `+`))
%p end if
%p end proc:
%p f(1) := 0:
%p seq(n - f(n), n = 1..100);
%o (Python)
%o from sympy import primefactors
%o def a(n, pn):
%o if n == pn:
%o return n
%o else:
%o return a(sum(primefactors(n)), n)
%o print([i-a(i, None) for i in range(1, 100)])
%Y Cf. A075860.
%K nonn
%O 1,4
%A _Rafik Khalfi_, Aug 18 2024